# 15 19 25 triangle

### Obtuse scalene triangle.

Sides: a = 15   b = 19   c = 25

Area: T = 142.1666056075
Perimeter: p = 59
Semiperimeter: s = 29.5

Angle ∠ A = α = 36.76992608408° = 36°46'9″ = 0.64217446652 rad
Angle ∠ B = β = 49.30774364255° = 49°18'27″ = 0.86105771113 rad
Angle ∠ C = γ = 93.92333027337° = 93°55'24″ = 1.63992708771 rad

Height: ha = 18.95554741434
Height: hb = 14.96548480079
Height: hc = 11.3733284486

Median: ma = 20.8998564544
Median: mb = 18.29661744635
Median: mc = 11.69440155635

Inradius: r = 4.81991883415
Circumradius: R = 12.52993621359

Vertex coordinates: A[25; 0] B[0; 0] C[9.78; 11.3733284486]
Centroid: CG[11.59333333333; 3.79110948287]
Coordinates of the circumscribed circle: U[12.5; -0.85772721461]
Coordinates of the inscribed circle: I[10.5; 4.81991883415]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 143.2310739159° = 143°13'51″ = 0.64217446652 rad
∠ B' = β' = 130.6932563575° = 130°41'33″ = 0.86105771113 rad
∠ C' = γ' = 86.07766972663° = 86°4'36″ = 1.63992708771 rad

# How did we calculate this triangle?

Now we know the lengths of all three sides of the triangle and the triangle is uniquely determined. Next we calculate another its characteristics - same procedure as calculation of the triangle from the known three sides SSS. ### 1. The triangle circumference is the sum of the lengths of its three sides ### 2. Semiperimeter of the triangle ### 3. The triangle area using Heron's formula ### 4. Calculate the heights of the triangle from its area. ### 5. Calculation of the inner angles of the triangle using a Law of Cosines ### 6. Inradius ### 7. Circumradius ### 8. Calculation of medians #### Look also our friend's collection of math examples and problems:

See more informations about triangles or more information about solving triangles.